"(He is) not really interested in signing a new contract and I think Man City have made a bid," said Curtis.
"So it's just a matter of time now before it happens and it's good for both parties. He's been terrific for us, to be fair, we've had two seasons out of him and he was superb in the Championship and virtually his goals got us promotion.
"And last year as well he wasn't maybe quite as effective as he was his first year - obviously it was a lot tougher opposition - but he's been absolutely magnificent.
"Like Joe we wish him all the best, but as long as the club keeps pushing forward that's the main thing.
"It obviously gives Scott the chance to settle in at his new club and it gives us the opportunity to buy a replacement for Scott."